So they fixed up the designator for the Cygnus mass simulator, but not for the Dove 1 nanosatellite, which is 39144 (they still have that catalog number mistakenly assigned to the Phonesat "Alexander"). I did already notify JSpOC about this a few weeks ago... I wonder if it will ever be corrected. I wonder how many other historical objects are misidentified. I guess now that everything has reentered it doesn't make too much difference.
I would say misidentifications run at the few percent level. As I slowly trawl the satcat with a fine toothcomb, I come across them here and there, like 05426, which is labelled as debris from a Soviet lunar lander test but is actually a despin weight from the French Eole satellite.
Or 06731 and 06732, labelled as Explorer 23 debris but actually S-2 retro-rocket covers from the Skylab launch.